Classifications

• • D—TEXTILES; PAPER
  • D02—YARNS; MECHANICAL FINISHING OF YARNS OR ROPES; WARPING OR BEAMING
  • D02G—CRIMPING OR CURLING FIBRES, FILAMENTS, THREADS, OR YARNS; YARNS OR THREADS
  • D02G1/00—Producing crimped or curled fibres, filaments, yarns, or threads, giving them latent characteristics
  • D02G1/02—Producing crimped or curled fibres, filaments, yarns, or threads, giving them latent characteristics by twisting, fixing the twist and backtwisting, i.e. by imparting false twist
  • D02G1/0206—Producing crimped or curled fibres, filaments, yarns, or threads, giving them latent characteristics by twisting, fixing the twist and backtwisting, i.e. by imparting false twist by false-twisting
  • D02G1/0226—Producing crimped or curled fibres, filaments, yarns, or threads, giving them latent characteristics by twisting, fixing the twist and backtwisting, i.e. by imparting false twist by false-twisting multiple false-twisting
• • D—TEXTILES; PAPER
  • D02—YARNS; MECHANICAL FINISHING OF YARNS OR ROPES; WARPING OR BEAMING
  • D02J—FINISHING OR DRESSING OF FILAMENTS, YARNS, THREADS, CORDS, ROPES OR THE LIKE
  • D02J1/00—Modifying the structure or properties resulting from a particular structure; Modifying, retaining, or restoring the physical form or cross-sectional shape, e.g. by use of dies or squeeze rollers
  • D02J1/22—Stretching or tensioning, shrinking or relaxing, e.g. by use of overfeed and underfeed apparatus, or preventing stretch
  • D02J1/228—Stretching in two or more steps, with or without intermediate steps
• • D—TEXTILES; PAPER
  • D02—YARNS; MECHANICAL FINISHING OF YARNS OR ROPES; WARPING OR BEAMING
  • D02J—FINISHING OR DRESSING OF FILAMENTS, YARNS, THREADS, CORDS, ROPES OR THE LIKE
  • D02J1/00—Modifying the structure or properties resulting from a particular structure; Modifying, retaining, or restoring the physical form or cross-sectional shape, e.g. by use of dies or squeeze rollers
  • D02J1/22—Stretching or tensioning, shrinking or relaxing, e.g. by use of overfeed and underfeed apparatus, or preventing stretch
  • D02J1/229—Relaxing

Definitions

• This invention relates to a process for the production of elastic voluminous crimped filaments from synthetic polymers especially from synthetic linear high molecular weight polyamides which comprises a two-step treatment of the filaments.
• the unstretched filaments were subjected to a false-twist crimping and stretching under heating and subsequently cooling the filaments. The stretching being effected without the aid of a Stretching pin.
• the filaments being subjected to a further false-twist crimping in the opposite direction, and a further stretching and cooling operation.
• the filaments being relieved of tension or subjected to a shrinking procedure.
• This invention relates to a process for the production of moderately elastic highly voluminous crimped filaments in which filaments of synthetic high polymers are subjected to false-twist crimping under the influence of heat, accompanied by stretching.
• crimped filaments can be produced from synthetic high polymers by false twisting under the influence of heat during the stretching process, followed by a bulking process.
• a stretching pin is located in front of the heating element in the stretching zone. In this process, fixing does not in itself have to satisfy the final requirements because a subsequent washing cycle is used to develop the crimp and to fix it under an appropriate increase in temperature.
• unstretched filaments of synthetic high polymers synthetic linear high molecular weight polyamides in particular, are subjected in a first stage to false twist crimping under heat, accompanied by stretching, and in a second stage to another false twist crimping operation in the opposite direction, accompanied by further stretching, and are then relieved of tension or shrunk.
• the first stage of the process is preferably carried out at a temperature from 160 to 180 C. and the second stage at a temperature from 130 to 150 C. In the first stage, stretching is from 200 to 250% and in the second stage from to 50%. Shrinkage or contraction amounts to from to 35%.
• the filament taken from the bobbin is continuously stretched and at the same time additionally false-twisted and heat-treated and 3,503,201 Patented Mar. 31, 1970 See then false-twisted in the opposite direction under tension and stretch. Finally, it is relieved of tension and so contracts.
• the crimped filament has no tendency to rotate and does not have to be twisted with another crimped filament tending to rotate in the opposite direction.
• the yarn thus obtained is moderately elastic, smooth and has little or no residual shrinkage.
• the filament is stretched in two parts, accompanied by twisting.
• the actual process of stretching takes place in the absence of any definite stretching point between the delivery rollers and the false twist spindle for the first part of the crimp in particular, so that the stretching zone in adjusted in dependence upon the cooling zone due to the temperature set in the heating element.
• the filament thus crimped and stretched twice is then subjected to a tension-relieving or shrinkage process.
• the twist applied to the travelling filament is from a half to once the normal twist and, in the second stage, is from once to one and a half times the normal twist (according to Heberleins twist formula as reported in Melliand Textil-berichte 3, 1966, page 239).
• the filament is stretched between the three delivery mechanisms in the heating unit in the absence of any definite stretching point.
• the twister does not perform the function of a stretching point, but merely transmits the torque to the cooled, stretched filament. For this reason, the filament is subjected to slight tension during fixing so that the crimp is formed normally. Residual shrinkage is reduced. A somewhat higher stretching ratio may also be used. Subsequent crimping in the opposite direction under tension ensures that the yarn is produced satisfactorily without rotation under the final degree of stretching, whilst the subsequent tension-relieving or shrinkage treatment makes it possible to produce filaments that can be satisfactorily processed.
• the crimped yarn has an appearance of the kind that can only be obtained in several operations with conventional machines (draw-twisting machines and special false-twisting machines incorporating an after-treatment unit).
• Convention machines draw-twisting machines and special false-twisting machines incorporating an after-treatment unit
• the following example shows more particularly the process according to the invention.
• EXAMPLE A filament of poly-e-caprolactam den.) is stretched in a ratio of 1:3.12 at C. in a heating tube (first stage) and at the same time is twisted in the S-direction by means of a twist spindle rotating at 1860 r.p.m. The filament, thus stretched and crimped, is twisted in the Z-direction in a second heating zone at 135 C. (2200 r.p.m.) and at the same time is stretched by 15%. The filament, thus stretched and false-twist crimped in two stages, is wound up under 15% shrinkage. This material is used for a knit fabric which is piece-dyed and finished.
• the filament thus crimped has a contraction through crimping (Melliand Textilberichte 5, 1966, page 439) of 25 to 30% and a residual shrinkage of about 8%.
• the filament does not have any tendency to stretch and may be processed as a monofilament. It is particularly suitable for use in monofilament processing, as a weft yarn in weaving and for weave-knit fabrics in the knitting field.
• the filament is not only relieved of tension, but is also continuously subjected to a shrinkage process at C., the residual shrinkage amounting to 2.5%. In this case, subsequent winding to relieve the yarn of tension takes below 35%.-
• the packages thus produced can be directly dyed by the creel process.
• a process for continuous production of moderately elastic highly voluminous crimped filaments from synthetic polymers, by false-twist crimping which comprises subjecting the unstretched filaments, in a first step, to a false-twist crimping under heat, and simultaneously stretching the filaments without the aid of a stretching pin and cooling, and, in a second step, subjecting the filaments to a further false-twist crimping operation under heat in the opposite direction and a further stretching without the aid of a stretching pin, cooling the filaments again and relieving the tension.

Landscapes

• Engineering & Computer Science (AREA)
• Textile Engineering (AREA)
• Mechanical Engineering (AREA)
• Yarns And Mechanical Finishing Of Yarns Or Ropes (AREA)

Applications Claiming Priority (1)

Publications (1)

Family

ID=7105590

Family Applications (1)

Country Status (7)

Cited By (1)

Citations (4)

• 1967
  • 1967-06-06 DE DE1967F0052610 patent/DE1660322B2/de active Granted
• 1968
  • 1968-05-24 CH CH769168A patent/CH482843A/de not_active IP Right Cessation
  • 1968-06-04 US US734230A patent/US3503201A/en not_active Expired - Lifetime
  • 1968-06-04 GB GB26436/68A patent/GB1182025A/en not_active Expired
  • 1968-06-05 NL NL6807885A patent/NL6807885A/xx unknown
  • 1968-06-06 BE BE716176D patent/BE716176A/xx unknown
  • 1968-06-06 FR FR1570785D patent/FR1570785A/fr not_active Expired

Patent Citations (4)

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